The present invention relates to electrical fuse-links for protecting electrical and electronic equipment.
British Pat. No. 1,304,629 in the name of Olvis Smeltzekeringen, Fabrick, N.V. and dated May 10, 1971 describes a fuse element consisting of a very thin or fine wire helically wound about a rigidified insulating core. The latter serves to support the wire and prevent sagging thereof and also provides handling strength for the fuse element. The core should be heat-resistive and be a good heat insulator and not maintain combustion, as well as being an electrical insulator and should be thin so that its heat dissipation can be substantially neglected. A thin rigidified core made from a fibre or filament of glass-fibre material has the required properties and its manageability allows the core to be sufficiently thin for its heat dissipation to be substantially neglected. The thin wire is wound onto the thin rigidified core in a multiplicity of closely spaced turns.
One disadvantage which has been experienced with the type of fuse element comprising a thin core supporting the windings of a thin fuse wire, is the relatively high resistance which results from the large number of turns of the wire wound on the core and an object of the present invention is to reduce or overcome this disadvantage.